Suction-pressure-regulating valve



"SUCTION PRESSURE-REGULATING VALVE Y' Filed July 22, 1940` V FzgffINVENTOR.

Fard'. FHEE er' ATTORNEY.

Patented May 4, 1943 SUCTION-PRESSURE-REGULATING VALVE Ferdinand F.Heiser, Wauwatosa, Wis., assigner.

to Automatic Products Company, Milwaukee, Wis., acorporation ofWisconsin Application July 22, 1940, serial No. 346,725

1 claim. '(01.137-153i This invention relates to an improvement insuction pressure-regulating valves for use with refrigerating systems.

An object of this invention is to provide a valve of this characterwhich is effective to maintain the evaporator pressure at a desiredlevel regardless of changes in load or variations in the suctionpressure on the outlet side of the valve. The evaporator temperaturemaybe maintained within very close limits.

One of the advantages of the valve is that it provides a means whichmakes it practical to operate two or more evaporators at diil'erenttemperatures with a single condensing unit. This is usually necessary inmultiple installations. While thermostatic expansion valves may be usedfor this purpose when the temperature diiferences are not too great,nevertheless when the temperature difference is over five or six degreesFahrenheit, then the use of a suction pressureregulating valve of thecharacter disclosed in this application is most desirable andadvantageous.

Another object of the invention is to provide a valve of this characterhaving these 4advantages, and which is simple, compact, and closelyorganized in its construction, reliable and efficient in operationIadvantageously adapted for use on systems of ooded, semiooded, or dryexpansion types, and also adapted to be manufactured with economy frommaterials and by means of facilities ordinarily available.

Another object of the invention is to provide a valve of this characterwhich may be set to maintain any one of a number of evaporator pressuresover a wide range.

Other objects and advantages reside in certain novel features of theconstruction, arrangement, and combination of parts, which will behereinafter more fully described and particularly pointed out in theappended claim, reference being had to the accompanying drawing forminga part of this specification, and in which:

Figure 1 is a view in central, vertical, longitudinal cross section,showing a suction pressureregulating valve involving the presentinvention; and

Figure 2 is a diagrammatic view of the control knob of the valve andillustrating the dial or scale which facilitates accurate adjustment ofthe valve to select the desired pressure setting.

to the tail or outlet end of the evaporator coil. Internally the valveis provided with a valve chamber I with which the inlet 8' is in opencommunication. An outlet fitting 8 is threaded into the lower open endof this chamber 1, as indicated at 9. A washer i0 between the ange of-the fitting and the valve body hermetically seals the connectionbetween these parts. The outlet fitting 8 is also externally threaded toadapt it to be connected to the suction side of the com pressor.

The upper end of the outlet fitting is provided with two counterbores II and i2, the counterbore Il being adapted to have'a valve seat I3fitted therein and secured thereto, and the counterbore I2 accommodatingthe head Il of the valve proper, designated generally at Il. The head Ilof the valve is provided with a facing i6 which may take the form of aiiat annulus of fibrous material, molded composition material, rubber,leather, or the like. This facing is held in position by a stud I1 whichhas its shank secured to the valve and its head overlapping the innerperiphery of the facing, and also by means of a retaining ring I8suitably secured to the periphery of the head of the valve and having aninwardly directed flange I9 overlapping the outer periphery of thefacing. The exposed portion of the facing coacts with the valve seat tocontrol the flow through the valve. l

The valve I5 has a valve stem 20 integral with its head Il, and slidablyntted in a tubular valve guide 2i. 'I'he lower end of the valve guide 2IReferring to the drawing, the numeral 5 designates the body ofthe valve.Integral with they is enlarged and flanged as at 22, and the en' largedportion thereof has a circumferential series of openings 23 to providefor con'imunication between the valve chamber 'I and the counterbore orspace I2 which accommodates the head of the valve. The under side of theflange of the enlarged end 22 of the valve guide 2| is engaged betweenthe upper end of the outlet fitting 8 and the lower ring 24 of astrainer, designated generally at 25. The upper ring 26 of the strainerengages an inwardly directed shoulder 21 integrally formed with thevalve body at the upper end of the valve chamber 'L The reticulated body portion of the strainer is suitably connected to the rings 2| and28.

A coil spring 30 encircles the valve guide 2l and has its lower endabutting the enlarged portion 22 thereof and its upper end abutting aanged washer 3i secured by a nut 32 and lock washer 33 to the upper endof the valve stem. The spring 30 is under compression and tends vtokbias the valve I 5 to open position and causes the `pressure index orscale.

rected\peripheral portion 39 of a. diap.' ragm or casing member 40. Theportion 59 oi' the dia- 10 phragm casing member 40 is spun'or rolledinto secure mechanical engagement and hermetic sealing relationship withthe periphery of the flange 38. The body of the casing 40 is providedwith a vertical cylindrical or'tubular extension 15 4| which isinternally threaded.

An adjusting knob, designated generally at 42, is provided and includesa cap 43. An exter-4 nally threaded sleeve 44 is combined with the cap43 and has its lower end open and its upper end 20 closed. The upperclosed end of the sleeve -44 fits against the under side of the-top ofthe cap and is rigidly interconnected therewith by virtue of provisionof dowel pins 45 which may be formed integrally with the under side ofthe cap and 25 41 has its head engaged with the top of the cap 30 andhas its threads interengaged with the bushing 56. The external threadsof the sleeve 44 are interthreaded with the internal threads of theextension 4l of the diaphragm casing. A

spring 48 is interposed between the upper mem- 35 ber of the diaphraghmpressure pad 35 and the under side of the closed upper end of thesleeve. By turning the knob the compression of the spring 48 may :bevaried. In order to facilitate adjustment of the spring 48, andconsequently to 40 determine the pressure which the valve will maintainin the evaporator, the extension 4| of the diaphragm casingis providedwith a series of graduations and numerals, designated at 50 in Figure 2.These graduations and numerals pro- 45 vide a pressure index or scale.Cooperable with this scale is a collar 5l which is carried by the sleeve44 and has a lower edge 52 cooperable with the graduations and with themembers of the is threadedly interconnected with the sleeve 44,

-and after it has been properly adjusted at the factory it is solderedin position ras indicated at 55.

'Ihe valve is also provided with a gauge con- 55 nectlon which isconstituted oi.' an internally threaded passage communicating withpassages 6I and B2 which lead to the valve chamber 1. A plug 63' isprovided for the passage B0,

and when this plug is removed the gauge (not 60 nected with the valvebody, being provided with 65 packing 65 and also with a cross slot 66 tofacilitate its manipulation by a screw driver or the like. A cap 61 isprovided for the outer end of Preferably the collar 5I 50 the openingwhich accommodates the needle valve, and aiter the gauge has served itspurpose and is removed, the needle valve may be turned up to shut of!communication between the passages 42 and BI, thereby precluding thepossibility of leakage when the gauge has been removed.

The suction pressure-regulating valve above described maintains an evenevaporator temperaature by controlling the pressures in the evaporator.As the load increases in the evaporator, increasing the temperature andthe evaporator pressure, the valve tends to open wider so as to maintainthe predetermined pressure setting of l.

Then when the evaporator the regulating valve. temperature begins tofall and the evaporator pressure tends to decrease, the valve begins toclose again, thus maintaining the original pressure setting of thevalve. The valve is of the throttling type tending to close offgradually as the evaporator pressure is reduced beyond a certain point.There is no sudden change to cause erratic operation of the balance ofthe system.

The scale 50, with which the lower edge 52 ot the collar 5| coacts, ispreferably graduated in pounds pressure, ranging from 10" vacuum tothirty pounds per square inch at which the valve operates. By turningthe knob down until the edge 52 of its collar 5l coincides with thedesired pressure setting, an immediate setting can be secured and it is.not necessary to wait several hours before the system has settled downsumciently to permit the valve to be adjusted to the proper pressuresetting. After the knob adjustment described has been made, and thesystem has had a short time to settle down, the exact pressure settingcan be secured by a gauge reading. The temporary setting will beaccurate within a pound or so.

While I have shown and described one construction in which the inventionmay be vadvantageously embodied, it is to be understood that theconstruction shown has been selected merely for the purpose ofillustration or example, and that various changes in the size,shape,.and arrangement of the parts may be made without departing fromthe spirit of the invention or the scope of the subjoined claim.

I claim:

A pressure-regulating valve comprising a valve body having a chamber, aninlet to said chamber, said chamber having an opening to the exterior ofsaid body, an outlet iitting inserted into said opening from theexterior thereof and connected thereto, two counterbores in saidfitting, a valve seat carried in one of the counterbores in said tting,a valve having a nat-faced head accommodated in the other of saidcounterbores and cooperable with said seat and having a stem, a tubularguide slidable on said stem and having a flange at one end, a springencircling said guide and reacting between said ilange and said stem,said valve, guide and spring being inserted as a unit into said chamberthrough said opening, said fitting being engaged with said ilange toposition said valve, guide and spring in said charnber, and a diaphragmcooperable with said stem to control the position of said valve.

FERDINAND F. I-IEISER.

